Comment 0 for bug 1644071

[Impact]

MAAS 2.1.2 is a new upstream bugfix release that includes various fixes that Ubuntu version of MAAS would benefit of. As per upstream CHANGELOG, MAAS 2.1.2 fixes:

LP: #1516065 Fix IPMI chassis config session timeout issue when configuring the boot device. Only error on PowerAuthErrors when configuring the IPMI chassis boot order.
LP: #1642996 2.x preseeds with {{escape.shell}} fail if not upgraded at 2.1.1
LP: #1643057 juju2 with maas 2.1.1 LXD containers get wrong ip addresses
LP: #1640300 Be defensive in the postgresql listener when a system notification is received for a none existent handler or missing listener channel.
LP: #1613862 Re-allow configuration of the port where to connect to postgresql.
LP: #1638575 Add two capabilities: bridging-interface-ubuntu and bridging-automatic-ubuntu.

[Test Case]
1. Install MAAS 2.0.0 or Ubuntu 2.1.0
2. Upgrade to MAAS 2.1.2
3. MAAS will continue to function as originally designed.

[Regression Potential]
Minimal. MAAS 2.1.2 has been CI'd and manually tested:

 - We perform new install package testing to ensure that the package is rock solid on fresh installations.
 - We perform upgrade testing from previous MAAS and Ubuntu Releases. At the moment we perform upgrade testing covering upgrades from MAAS 2.0. The upgrade ensures that MAAS after the upgrade is up and running with no issues.
 - We have performed CI testing to ensure there are no regressions.